A week ago AE was running fine, but in the last few days, I must have enabled or did something to chop its performance by 75%. I know this is really broad, but do you guys know of any thing on the top of your head that may or could be enabled to do this?

Also, while rendering, my ENTIRE computer is super laggy, just typing this text right now, for example, is laggy. I used to ALWAYS hit render, and then browse the web, watch videos, etc... but now it's unbearable. Also, it isn't just when i do a final render. It also occurs when I skip to a single frame in the comp and it tries to render it(goes really slow)

Thanks for your suggestions. I opened a different composition and speeds were fine. So I'm not sure what to say. I even removed all effects from the first comp and it was still super slow. If it happens again I'll report.